Abstract: From the perspective of geophysical field, applied integra ted geophysical a nd geochemical explora tion techniques reveal that Qaidam Basin has double basement structures. The upper is the folded basement and the crystallized basement exists in the deep part. The thickness v ariation of the crysta llized basement controls the upwa rpingdownwarping pattern of the ba sin. The folded ba sement lithology has obvious zoning cha racteristics and it va ries a lot in different zones. As a result, different zones have different deformed cha racteristics. The zonality is determined by the fracture of deep structure. The front belt of mounta in is a n important area for oil and ga s exploration in Qaidam Basin, however, there are still a lot of limita tions on the cognition of it due to its sophisticated topographic and geologica l conditions. The structura l cha racteristics of the foothill belt have been basically known, some piedmont depressions a nd overthrust nappe zones ha ve been discovered, and the exploration area of Qa idam Basin has been widened as well on the basis of the application of the integrated geophysical and geochemical exploration techniques

Key words: deep structure, deep fa ult, basement lithology, foothill belt, geophysical a nd geochemica l explora tion techniques, Qaidam Ba sin